1. Field of the Invention
The present general inventive concept relates to an ink composition including a siloxy group-containing silane-based compound, a colorant, and a solvent, and an ink cartridge and an inkjet recording apparatus including the composition. More particularly, the present general inventive concept relates to an ink composition which, as a result of using a siloxy group-containing silane-based compound, prevents production of ink foam or bubbles in a cartridge when an inkjet printer is operated, induces a rapid elimination of foam or bubbles produced, exhibits a stable initial ink ejection behavior owing to good ink flowability, enhances durability characteristics, such as bleeding resistance to improve the quality of printed images, and prevents nozzle clogging, and an ink cartridge and an inkjet recording apparatus including the composition.
2. Description of the Related Art
Recently, with an increase in need/demand for coloration of hard copies in the field of image processing, etc., various methods of producing color hard copies have been developed. Examples of these methods include dye-sublimation recording, thermal wax transfer recording, inkjet recording, electrophotographic recording, and thermally processed silver recording.
In inkjet printing, ink droplets are ejected from nozzles of a recording head of an inkjet printer onto a recording medium, such as a paper. The ejected droplets form points called “dots” to create characters and images. The advantages of inkjet printing over other printing methods are its low cost, high quality, and ability to easily produce color images.
Thus, inkjet printers capable of simply printing at homes and offices have been widely been used. Inkjet printers that can provide image quality comparable to silver images have also been developed.
Ink used in inkjet printing is prepared by dissolving or dispersing a water-soluble dye or pigment into a solvent including water and a water-soluble organic solvent. If necessary, an additive, such as a surfactant, may be added.
In order to accomplish good inkjet recording for a long time, water-based ink for inkjet printing must satisfy the following requirements: characteristics such as viscosity, surface tension, and density, should have appropriate values, nozzle clogging in an inkjet recording apparatus, precipitate formation due to heat or the like, and a change in physical property values should not occur, and recorded images should have excellent water-repellency and light fastness.
When a large amount of ink is stored in a large capacity ink reservoir used in an inkjet system for a long time, foam or bubbles may be produced in the ink. Furthermore, when air is dissolved in ink, ink may produce foam or bubbles. In addition, when an ink circulation system is incorporated in a print cartridge, foam or bubbles may be produced in the print cartridge. The foam or bubbles must be easily removed from ink or be prevented from being produced. Thus, it is necessary to enhance the defoaming or antifoaming property of ink.
However, in conventional ink compositions, foam or bubbles are easily produced due to a surfactant used as a component of ink, and thus, the requirements of an ink composition are not satisfied.
In view of this problem, Japanese Patent No. 3,078,184 discloses addition of a fluorine- or silicon-based polymer to ink.
However, such a polymer is poorly soluble in ink, and thus, it is necessary to use a solvent that can disperse or dissolve the polymer. Moreover, such a solvent and polymer have poor miscibility with standard water-soluble additives forming ink. Thus, layer separation and solidification easily occur in the ink, and when the ink is not used for a long time, the silicon polymer and the ink are rapidly dried, thereby rapidly increasing the viscosity of the ink, resulting in nozzle clogging due to ink hardened at a surface of a nozzle of a printhead.
An ink composition and related technology capable of preventing the production of ink foam or bubbles in a cartridge, rapidly eliminating foam or bubbles produced, exhibiting a stable initial ejection behavior, enhancing durability characteristics, such as bleeding resistance, to improve the quality of printed images, and preventing nozzle clogging has not yet been provided.